Abstract: Organometallic ceramic precursor binders are used to fabricate shaped bodies by different techniques. Exemplary shape making techniques which utilize hardenable, liquid, organometallic, ceramic precursor binders include the fabrication of negatives of parts to be made (e.g., sand molds and sand cores for metalcasting, etc.), as well as utilizing ceramic precursor binders to make shapes directly (e.g., brake shoes, brake pads, clutch parts, grinding wheels, polymer concrete, refractory patches and liners, etc.). A preferred embodiment of the invention involves the fabrication of preforms used in the formation of composite articles.

Abstract: A method of and apparatus for forming a pressed body (54) with a bore (56) therein and with a notch (58) in the exterior surface thereof. The body (54) is formed by isostatically pressing particulate material (52) in an elastic mold (14) so that the material (52) is compacted into a self-supporting mass. Used in conjunction with the elastic mold is a mold closure and core holder member (32) to which is fixed a rigid core (42) and a resilient notch defining bar (44).

Abstract: A ceramic insulator and a method for the production thereof are disclosed. The method comprises the steps of pressing ceramic batch around a contoured arbor having at least two longitudinally extending fins to form an outer piece having a bore with grooves therein corresponding to the fins, removing the arbor from and contouring the piece to a desired external shape, pressing ceramic batch to form an inner piece, and contouring the inner piece to fit within the bore of the outer piece. The inner piece is then positioned within the bore of the outer piece and both pieces are fired whereby the insulator is produced in which the contoured surface of the inner piece closes the grooves in the bore of the outer piece to form slots extending longitudinally within the ceramic insulator. Also disclosed is a method which involves firing the inner piece, positioning the fired inner piece within the bore of the unfired outer piece, and then firing both pieces together.

Abstract: An improved method for producing a ceramic insulator is disclosed. The method comprises the steps of charging ceramic batch into a longitudinally extending die in which stepped arbors are supported by a plunger, forming a blank by pressing the batch between the arbor plunger and an opposing plunger, ejecting the blank and removing the arbors therefrom, contouring the blank to a desired shape, and firing the contoured blank. The insulator has a length-to-diameter ratio greater than 3:1 but not greater than 8:1; the improvement constitutes controlling the relative movements of the opposing plungers with respect to the longitudinal wall of the die during pressing of the blank so that at least 80 percent of the total plunger movement is in the direction of decreasing arbor diameter whereby variations in the end-to-end density of the insulator are minimized.

Abstract: A high-silica ceramic glaze, having a low coefficient of thermal expansion, suitable for application to alumina bodies, is disclosed. The glaze comprises, by weight percent, about 50 percent SiO.sub.2, from 5 to 8 percent Al.sub.2 O.sub.3, from 6 to 12 percent B.sub.2 O.sub.3, from 2 to 15 percent BaO, from 5 to 8 percent SrO, from 4 to 6 percent CaO, from 2 to 8 percent MgO, from 1 to 2 percent ZnO, and about 5 percent total of Na.sub.2 O, K.sub.2 O, Li.sub.2 O, and minor impurities.